Using two spudgers, place the pointed tips at each end of the U-shaped snap ring located under where the home button assembly was.

Remove the snap ring by pushing down with both pointed objects on each side of the ring simultaneously, it should pop off.

Be careful not to lose the snap ring because it can be lost easily.

To replace the snap ring, rest it above the home button peg using tweezers so the open side rests on the peg. Then use the flat end of the spudger and push firmly down on the snap ring to snap it back onto the peg as shown in the last picture.